RAMALLAH: Four Palestinian prisoners detained in the West Bank during a sweeping arrested campaign by Israeli military forces have announced that they will launch hunger strikes until they are guaranteed their release, Ahlul Bayt News Agency reported on Friday. The four men, all of whom are from Jenin, are being held under administrative detention, presently without charges or trials. At least one of the prisoners, Jafar Ezzudin, participated in a previous hunger strike. At least three additional Palestinian prisoners were already on hunger strike in Israeli military prisons. Prisoner rights organization Addameer is concerned about their deteriorating health, it said in a statement released on Tuesday. Ayman Shawarna, who has been on hunger strike for 149 days, ingesting only water, stated he is ready to “intensify" his hunger strike, according to Ma'an News Agency. He is presently being held in a military clinic, shackled to his hospital bed for the vast majority of the day. He has reportedly lost 38 kilograms since he stopped taking food. Samer Issawi, another hunger striker who on Tuesday hit 118 days, also stopped accepting water on November 21. He is fainting regularly, monitors report, and has sustained several injuries. Issawi's health has quickly declined, and his weight has fallen to a mere 46 kilograms. Lawyers say he suffers from back and leg pain, as well as alarmingly low blood pressure. Both of these prisoners, released in the 2011 Gilad Shalit prisoner swap that brought home 1,027 Palestinians, are imprisoned in administrative detention without charge. A third administrative detainee, Oday Keilani, joined the hunger strikers and has not taken food for 36 days. He is reportedly suffering from pain in various parts of his body. His sentence was extended for an additional four months and his lawyers are continually denied access to his case, which Israeli prison services say contains “secret information," reported Ma'an. On Tuesday Palestinian prisoners from across the entire political spectrum launched a one-day hunger strike in solidarity with Issawi and Shawarna. Ahrar, a prisoner rights organization in Gaza, estimates that thousands of prisoners have joined in. Ahrar added that it holds the Palestinian Authority responsible for the media indifference towards the plight of Palestinian prisoners and their struggle for better treatment, access to family visits, medicine and medical resources, among other demands. As recently as September, Israel held 4,606 Palestinian political prisoners, 212 of which were in administrative detention without charge. Last Spring, over 2,000 Palestinian prisoners launched a mass hunger strike that grabbed international attention.